Nostalgia
by The-Penny-Tails
Summary: Someone from Hotch's past has returned, and is willing to go to extreme measures to get exactly what they want from the Unit Chief. Unfortunately for the team, that means having to protect a now seven-year-old FBI agent with a foggy memory, whilst having no clue as to who this mysterious Unsub could be. Warning: child abuse.
1. Prologue

**-o-**

Aaron Hotchner did not understand adults. They were strange, foreign beings; far too peculiar to have a reasonable conversation with. They spoke about weird things, and did odd rituals that held no importance in the young lad's eyes. It seemed that adults were just incapable of knowing what was truly significant in life - candy, play time, and coins.

Holding the soft bear that had been given to him an hour or so ago close to his chest, Aaron didn't know why he wasn't more afraid. These people were complete strangers... weren't they? He would certainly have remembered if he'd seen the really colourful woman with the glasses before, right? He knew he hadn't. But, for some reason, he felt like he knew all of the people that kept making a fuss over him.

Biting his lip, he continued to remain quiet. Everyone - even the weird dude with the stupid hair - had all tried talking to him, asking him questions and different things like that. He hadn't answered, of course. Aaron might have been a kid, but he wasn't an idiot. His mom had taught him that revealing secrets to people who weren't family was wrong. His mouth would remain sealed shut, and there was nothing these people could do about it.

-v-

"There has to be another explanation."

Rossi shook his head.

"Morgan's got a point. People don't just... transform back into children," Kate said, glancing through the glass at the boy. Scepticism was written all over her face, but there was a hint of hesitance in her eyes, as though she didn't know what to believe anymore.

"Look," Rossi started, waiting until he had the entire team's attention. He gestured towards the two people sitting in the guest office. "The camera clearly shows Hotch getting hit with whatever it was the Unsub was carrying, and this kid dropping to the floor where he should have been. _You_ witnessed it." He jabbed a finger at Reid.

"Are you telling me that you're lying about what you saw?" he asked, raising an eyebrow at the younger profiler in accusation.

"What? No!" Reid exclaimed, tone affronted. His expression lowered in denial. "I just... it doesn't make any sense to me."

"It doesn't make sense to any of us, kid," Rossi said, gaze unconsciously moving back to Garcia and the boy sitting at her side. The frown marring Rossi's face would undoubtedly become a permanent fixture if no one could think up a plausible explanation soon.

But what could explain it? If the kid was an impostor, the Unsub had done one hell of a job at getting the best look-a-like possible. The boy could easily be Jack's brother. He looked almost identical, except with darker hair, a slimmer build, and dimples. Considering they had no photos of Hotch as a child to compare with - the man was far too private for his own good, sometimes - they had nothing but their observations of the boy to go on.

Also, if the kid were faking, then where on Earth was their Unit Chief? People didn't just vanish into thin air. Did they?

"The best thing we can do is get the kid to talk," Rossi said after a moment. He saw Morgan nod out the corner of his vision, but he could still see the disbelief on his face. Heck, the entire team were on the fence about this one.

He sighed, before opening his mouth to address his friends once more. "Anyone care to volunteer?

-v-


	2. Chapter One

-v-

_"FBI!"_

Drawing in a deep breath, Rod closed his eyes. The images were so vivid, so clear in his mind; even if he wanted to drown them out and forget - he didn't - that would be impossible to do.

_"Put the weapon down."_

That voice was like liquid velvet to his ears - warm and soothing, but with a hint of delicacy. Men's vocals were gruff, yes, but his had a touch of something else, something he couldn't quite describe. Rod longed for it.

_Rod turned around with a small smile brightening his features, completely ignoring the gun pointing at his vulnerable chest._

Seeing the man up close was something Rod had not been prepared for. He'd had to contain his excitement at the time, shutting down on the urge to let joyful hysteria over take his form. Sure, he'd seen Aaron on television countless times, but that was nothing compared to having him standing right there within touching distance.

Curling his fingers around the pencil he was holding, Rod felt it beginning to snap in his tight grip. He was putting far too much strain on the poor, unsuspecting wood.

_"It's not a weapon, Aaron."_

He sighed. If only the circumstances had been different, he wouldn't have needed to resort to creating the device in the first place. But he'd had no choice. Life was an ass, and sometimes illegal actions were necessary.

_He hadn't meant to use the agent's name, but it had rolled off his tongue so naturally. Of course, Aaron hadn't even flinched at Rod's use of it._

Gritting his teeth, Rod let his anger get the better of him and broke the pencil in half. Allowing it to fall from his hand in pieces, he ignored the soft tapping as the wood connected with the hard floor beneath his feet.

_Before Aaron could tell him once again to put the device down, Rod pressed the button._

_It was only then that he realised his mistake._

_"Hotch!"_

Spinning on the spot, Rod let out a scream of frustration. His dark eyes located the nearest object, and he picked it up in one smooth movement. Without an ounce of hesitation, he flung the cup at the wall, watching as it smashed into sharp, broken segments. The satisfaction of that release lasted only seconds.

That stupid bastard of an agent should not have been there. He'd been hiding, waiting to pounce, and Rod hadn't spotted him until it was far too late. The freakin' coward should have been somewhere - _anywhere_ \- else. Rod had planned the events out perfectly; to have it ruined by a child was beyond insulting.

Aaron should have been _his_. He knew the device had worked - the hit had been dead on, and he'd seen the small body drop - but he hadn't been able to take his prize. He'd had to retreat, to run away so that stupid agent couldn't arrest him.

Snarling, Rod clenched his hands into fists. This was far from over. There wasn't an FBI agent in the world that would stop him from getting what he wanted. He'd waited too long to fail now.

-v-

"Aaron."

Rossi made a mental note to give JJ a high five when this was all over. The woman was truly a miracle worker. Where Kate, Reid, Morgan, and he had all failed, she had come out in triumph. Perhaps it was the fact that she had Henry that made her more capable for this job. No one else on the team could really say they had a lot of experience with a young boy. Well, no one except Hotch.

Regardless, whatever it was that enabled JJ to succeed, Rossi couldn't give a damn, because she'd got the boy to answer a question. Even Garcia hadn't been able to, and she'd spent the better half of an afternoon with him cooped up in this office.

"When were you born, Aaron?" JJ asked, a smile lighting up her face.

Aaron's expression creased into a frown as he eyed Rossi with caution. It was obvious that he was unhappy with this arrangement. In all honesty, so was Rossi. If he could wait outside, he would. The only problem was the fact that, if they wanted to gauge whether or not the boy was being truthful, it was far easier to do with two people rather than just one. Obviously, it would be beneficial to have the entire team in the room, but they didn't want to scare the poor kid any more than was necessary.

"November 2nd, 1965."

Rossi raised an eyebrow, more out of habit than anything. "Ah, so you're 49 years old?"

Clearly, that was the wrong thing to say. The sarcasm probably didn't help, either. Aaron's features twisted into an expression that Rossi had seen many times; it was recognisable, and something he would often get to witness when Hotch thought someone was being immensely stupid. The only difference was subtlety - the kid had none whatsoever. Rossi had to force himself not to fidget in his seat. That expression was _far_ too familiar for his liking.

"_No_. I'm _seven_," Aaron replied, tone easily betraying what he thought of Rossi's intelligence, or lack thereof. Rossi sighed. This was not going well, and he seemed to be making things worse. How was that even possible?

Glimpsing JJ's expression from the corner of his vision, Rossi turned to her with bemusement as she proceeded to smirk. Rossi stared. What was she up to? Waiting patiently, and keeping his mouth shut so he couldn't say anything else that could jeopardise their chances of getting answers, Rossi watched as she leant forwards, almost as if she were about to divulge some horrible secret.

"He's not very good at math," she whispered, shaking her head in an oddly sympathetic way. Rossi understood what she was doing instantly. Now he owed her _two _high fives.

Taking his cue when Aaron's mouth twitched upwards slightly at JJ's jab, Rossi stood up abruptly, knocking the table slightly. Aaron jerked backwards in obvious surprise, and... was that a hint of fear in his gaze? Rossi ignored it for now. Folding his arms and masking his features into an expression of anger, he glared at JJ.

"I am excellent at math, agent. Go on, ask me anything to do with numbers."

JJ glanced up at him, her smirk still in place. There was a sparkle in her eye, almost as though she were thanking him for catching on so quickly.

"Okay. Tell me what year it is."

Rossi grinned. "Easy. 2015."

This produced the desired response: Aaron let out a snort of amusement as his apparent fear disappeared, and JJ allowed herself to force out a chuckle. Shaking her head once more, she turned back to Aaron and cringed, hard.

"See what I mean?" she said, gesturing towards Rossi with her head. Aaron nodded, albeit slowly, and Rossi knew that JJ would take the opportunity given to her before it could be lost.

"I bet you know what the date is, don't you, Aaron?" she asked. Fake curiosity was seeping out of her every pore, but Aaron didn't know that. To him, the emotion was completely genuine, and that was what they needed. Gaining the boy's trust was a must.

This time, Aaron's nod was a lot faster.

"Okay then, why don't you tell me?" Rossi's grin had disappeared, and he was watching the two with intense focus. He had a strong feeling as to what the boy's answer would be in regards to what year it was, but he and JJ needed verbal confirmation to see if their assumptions were correct.

Aaron's dark eyes narrowed as he glanced back at Rossi. The look held an air of smugness about it, typical for a boy his age, but there was something behind the gaze that Rossi was having trouble identifying. It was almost as if Aaron had a grudge against him for being a man, considering he hadn't looked at either Garcia or JJ in such a manner. The expression was disconcerting to say the least.

"June 20th, 1973."

Ah, so he had the correct day, just not the correct _year_.

Now that was interesting.

-v-


End file.
